Intel 815 - Component Features; Graphics Memory Controller Hub (GMCH); Figure 2. GMCH Block Diagram

Introduction
R
18 Intel
®
815 Chipset Platform Design Guide
1.3.2 Component Features
Figure 2. GMCH Block Diagram
System bus (66/100/133 MHz)
Processor I/F
System
memory I/F
AGP I/F
Local memory I/F
Hub I/F
Data
stream
control &
dispatch
Primary display
Overlay
H/W cursor
3D pipeline
2D (blit engine)
RAMDAC
FP / TVout
Internal graphics
GPA
or AGP
2X/4X
card
Hub
SDRAM
100/133
MHz, 64 bit
Monitor
Digital
video out
comp_blk_1
1.3.2.1 Graphics Memory Controller Hub (GMCH)
• Processor/System Bus Support
 Optimized for Intel
®
Pentium
®
III processors (CPUID = 068xh) at 133 MHz system bus
frequency
 Support for Intel
®
Celeron™ processors (CPUID = 068xh); 66 MHz system bus
 Supports 32-bit AGTL or AGTL+ bus addressing
 Supports uniprocessor systems
 Utilizes AGTL and AGTL+ bus driver technology (gated AGTL/AGTL+ receivers for
reduced power)
• Integrated DRAM controller
 32 MB to 512 MB using 16-Mb/64-Mb/128-Mb technology
 Supports up to three double-sided DIMMS (six rows)
 100 MHz, 133 MHz SDRAM interface
 64-bit data interface
 Standard Synchronous DRAM (SDRAM) support (x-1-1-1 access)
 Supports only 3.3V DIMM DRAM configurations
 No registered DIMM support
 Support for symmetrical and asymmetrical DRAM addressing
 Support for x8, x16 DRAM device width
 Refresh mechanism: CAS-before-RAS only
 Support for DIMM serial PD (presence detect) scheme via SMbus interface
 STR power management support via self-refresh mode using CKE